1. Field of the Invention
The present invention concerns the transformation of a digital signal, such as digital filtering.
2. Description of Related Art
Numerous digital filtering methods and devices are known. Digital signal analysis filterings are envisaged here by way of example. Amongst such filterings, wavelet transformations are more particularly envisaged.
These filterings are generally subassemblies integrated into the coding and/or decoding assemblies. They often require a large amount of random access memory or buffer space for storing the data in the course of processing. For example, for image processing, the most conventional solutions for producing the wavelet transform consist of loading the entire image to be processed into memory and then effecting the different filtering steps. The memory space is then so large that this makes it difficult to implement such filterings in appliances such as photographic appliances, facsimile machines, printers or photocopiers for example.